Novel Anti-Inflammatory Bioactive Peptide Derived from Yak Bone Collagen Alleviates the Skin Inflammation of Mice by Inhibiting the NF-κB Signaling Pathway and Modulating Skin Microbiota.

Food-derived anti-inflammatory bioactive peptides have garnered significant attention due to their wide sources, easy absorption, and high biosafety. Our preliminary study identified a novel anti-inflammatory peptide GPAGPSGPAGKDGR (GR14) from yak bone collagen, which significantly alleviates lipopolysaccharide-induced inflammatory responses in HaCaT cells, demonstrating potential applications in improving skin inflammation. The objective of this study is to validate the anti-inflammatory effects of GR14 at the skin level in living animals and elucidate its mechanism of action. In this study, a 1-chloro-2,4-dinitrobenzene (DNCB)-induced skin inflammation mouse model was established. Results indicated that the GR14 intervention significantly improved skin manifestations and serum inflammatory cytokine levels in model mice. Compared to the model group, the high-dose treatment group demonstrated 33.61%, 40.55%, 22.18%, and 31.25% reductions in interleukin-6, interleukin-1β, tumor necrosis factor-α, and nitric oxide levels, respectively. Western blotting confirmed that GR14 intervention significantly inhibited the phosphorylation levels of P65 and IκB in the NF-κB signaling pathway. Microbiota analysis revealed that GR14 intervention effectively restored the significant decreases in Staphylococcus and Mammaliicoccus abundances caused by DNCB stimulation, returning the skin microbiota structure to normal status. These findings suggested that GR14 alleviates skin inflammation in model mice, potentially through suppressing the NF-κB signaling pathway and reshaping the skin microbiota structure. This study would promote the application of GR14 as a bioactive ingredient in the fields of functional food and functional cosmetics.